NEW YORK (CBSNewYork) — Men with guns swarmed one World Trade Center Saturday morning, but luckily it was all just a drill.

Gun shots could be heard during the multi-agency drill, CBS 2 reported.

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The “active shooter drill” used mock gunmen firing paint bullets.

The drill is designed to test how the NYPD, Port Authority, MTA, and Homeland Security would coordinate and interact during a real attack.

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The drill follows several recent security issues at the site.

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